Edge-holding device for sheet-glass machines



May 6, 1924. 1,492,942

H. G. SLHNGLUFF EDGE HOLDING DEVICE FOR SHEET GLASS MACHINES Filed Feb. 26, 1923 3 Sheets$heet 1,

May 6 i924.

11,492,942 H. G. SLINGLUFF EDGE HOLDING DEVICE FOR SHEET GLASS MACHINES Filed Feb. 26 1323 3 Sheets-Sheet P May 6, 1924. 1,492,942

H. e. SLIINGLUFF EDGE HOLDING DEVICE FOR SHEET GLASS MACHINES Filed Feb. 26 1923 3 Sheehs-$heet .3

Patented May 6, 1924.

UNITED STATES PATENT OFFICE.

HARRY G. SLINGLUFF, 0F MOUNT VERNON, OHIO, ASSIGNOR TO PITTSBURGH PLATE GLASS COMPANY, A CORPORATION OF PENNSYLVANIA.

EDGE-HOLDING DEVICE FOR SHEET-GLASS MACHINES.

Application filed February 26, 1923.

T 0 all whom it ma-y concern:

Be it known that I, HARRY G. SLINGLUFF, a citizen of the United States, and a resident of Mount- Vernon, in the county of Knox and State of Ohio, have made a new and useful invention in Improvements in Edge-Holding Devices for Sheet-Glass Machines, of which the following is a specification.

The invention relates to apparatus for use with a glass sheet drawing machine, and has for its objects the provision of an im proved means for automatically preventing the edge of the sheet from moving in during the drawing operation and thus gradually reducing the width of the sheet. Briefly stated the device comprises a pair of spaced fingers at each side of the sheet with mechanism for giving the fingers a stroke down into the base of the sheet and then outwardly so as to thinthe edge at such base, at the same time chilling the glass at this point and working it outward. The mechanism is arranged to give the fingers their stroking movement at such intervals as may be found necessary, depending on the speed of draw and the condition of the glass. An interval of rest in the movement of the fingers is preferably provided when they are above the glass bath at their posi tion of travel which is most remote from the bath in order to give the fingers an opportunity to cool, thus avoiding the necessity of providing cooling means which would involve further complication. The specific apparatus illustrated is only one of a large number which might be employed for giving the fingers the desired path of movement, and the path of movement itself might be varied considerably, although that illustrated is preferred. Referring to the drawings Figure 1. is a diagrammatic side elevation showing the drawingapparatus with which the edge holding device constituting the present invention is preferably used, such drawing device being described and illustrated in my copending application, Serial No. 621,184. Fig. 2 is aside elevation of one of the edge holding devices in position of use. Fig. 3 is an end elevation of the device in Fig. 2. Fig. 4: is a section on the line IVIV of Fig. 2. Fig. 5 is a detail end elevation. of the intermittent driving Serial No. 621,186.

gear employed and Fig. 6 is a section on the line VI-VT of Fig. 2.

Referring first to the general arrangement of parts as illustrated in Fig. l, the principal parts of the drawing apparatus .may be enumerated as follows:

1 is the drawing tank or extension carrying a molten bath of glass, 2 in communication with a suitable melting tank, not shown; 3 and 4 are endless belts, preferably of asbestos fabric for continuously drawing the sheet of glass 5 from the molten bath; 6 and 7 are the driving pulleys for the belts, such belts being driven from a suitable motor, not shown; 8 and 9 are solid steel bars circular in cross section lying in the lower ends of the belts and serving by reason of their weight to hold the belts in tension;' 10 are a series of rolls back of the inner flights of the belts for pressing the belts against the glass, such rolls being yieldingly held inward by means of springs or weights, not shown; 11 and 12 are pairs of driven rolls covered with asbestos for assisting in the pulling of the sheet; and 13 is one of the edge holding devices to which the present invention is particularly directed, it being understood that such edge holding devices may be used in connection with any form of drawing mechanism, although the one as briefly illustrated and described is preferred.

It will be understood that an edge holding device, such as that shown in Fig. 2 is applied at each side of the sheet, but for brevity of description and illustration only one of such devices is shown. The frame work of the device consists of a plate 14 supported from the gusset plate 15 which in turn is riveted to the lower end of the angle iron 16' constituting a part of the framework of the drawing mechanism. In order to provide for the adjustment of the edge device and meet varyii'ig conditions, the framework is preferably supported adjust-ably by clamping devices consisting of bolts 17 and 18 provided with wing nuts 19 and 20 mounted in the slots 21 and 22 of the gusset plate. This permits the framework to be moved in and out and tilted around the bolt 17 as an axis.

The stroking device for holding out the edge of the sheet 5 consists of the pair of fingers 23 spaced apart so as to straddle the edge of the sheet and having their lower ends curved as indicated at 24. The ends 24: are spaced apart a distance such that when they reach the position indicated in Fig. 2, they engage the tapering base 25 of the sheet as indicated in Fig. 3, thus thinning it and also chilling it so that on the outward movement of the fingers, there is a tendency to pull the base of the sheet laterally, thus counteracting the tendency of the sheet to narrow. The upper ends of the fingers merge into. each other in the part 26 which is secured removably to the lever 27 by means of the bolts 28. This permits of the ready removal of the fingers for replacement and repair. The lever 27 is supported upon a stud 29 shown in detail in Fig. (3. This stud carries a nut 30 at each end and has a square portion 31 at its central portion which fits into a slot 32 in the plate 14-. The plate 14: is supplemented and st-ifiened by another plate 33 shown in cross section in Fig. 6 and also slotted to receive the square portion 31 of the stud. This plate 33 extends over only a portion of the plate i l as indicated at Fig. 2, being secured rigidly thereto by means of the rivets 34. The stud and lever 27 carried thereby are reciprocated by means of a pair of parallel bars 35 which engage the stud as inclicated in Fig. (3. The part 36 shown in Fig. 6 is merely a spacing collar integral with the stud 29.

' The left hand end of the lever 27 is di rected upwardly in an oblique direction as indicated in Fig. 2 and provided with a stud 37 which engages in a cam recess cut through the frame plate 14 and its reinforcing plate 33. Mounted in this cam recess 38 is a latch 39 pivoted upon the lower end of the gusset plate 15 by means of the pin 40. This latch is weighted so that it normally assumes the position indicated in Fig. 2.

The pair of parallel bars 35 are pivoted at their rear ends upon a pair of studs 41 as indicated in Fig. 4:, such studs being screwed into the sides of the cross head 42. This cross head rides upon a guide formed upon the lower edge of the plate'lt by riveting to such plate the bars 43. Secured into the lower side of the cross head is the stud 44L to which is pivoted the forward end of the coi'inecting rod 45, a washer 46 with acotter pin 47 serving to prevent the end of the connecting rod from slipping off of the stud. The left hand end of the connecting rod is pivoted to the crank pin 48 secured to the crank disc 49. The crank disc is mounted upon a stub shaft 50 connected by means of a knuckle joint 51 with a shaft 52. The shaft 52 is provided with a pinion which is driven intermittently from the gear 5d mounted upon the drive shaft 55. The gear 54 is blank over twothirds of its periphery as indicated in Fig. 5 so that the pinion 53 and the stroking mechanism driven thereby are in motion only about one-third of the time. The parts are arranged so that during the period of rest, the ends 24 of the stroking fingers are at the position c of Fig. 2, in which position they are in their most remote location with respect to the glass bath. This arrangement tends to avoid over heating of the fingers which would interfere with the operation of the device when the temperature reached a point at which the glass adhered to the fingers. The arrangen'rent described involving the period of rest avoids the necessity of using cooling devices in connection with the fingers such as would otherwise be necessary.

In operation, the rotation of the crank disc 49 causes the reciprocation of the bars and the lever 27 carried thereby and in the course of such reciprocation, the cam recess 38 in engagement with the pin 37 at the upper end of the lever 27 causes the fingers 23 to follow the cycle of movement which has been found most desirable. This cycle of movement is illustrated diagrammatically by the dotted line figure of Fig. 2 touching the ends of the fingers 23. Starting with the parts in position shown, the movement of the bars 35 to the left causes the points'of the fingers to follow the dotted line path marked a which continues until the pin 37 reaches the point a of the cam recess. In other words, the cam fingers are moved substantially horizontally and this tends to drag the tapered base of the sheet to the left and prevent its narrowing. A further movement of the bars 35 to the left causes the pin 37 to follow the surface I of the cam recess and during this period, the ends of the cam fingers follow the dotted path 6 bringing them to the position marked 0. This is the position of rest of the apparatus at which time teeth of the driven pinion 53 are out of engagement with the teeth of the gear 54. When the teeth of the two gears again come into contact after the period of rest, the bars 35 are moved to the right, the pin 37 being at this time at the point (Z and the latch 39 having swung to the position illustrated. On a further movement of the bars to the right the pin 37 moves along the portion of the latch marked a", while the ends of the fingers 23 move along the portion of the path marked 0 on the dotted figure. This brings the figures over the edge of the glass sheet and on a further movement of the pin 37 along the surface f of the latch, the fingers move downward to the position illustrated, following in such movement, the portion of the path marked f.

v The foregoing movements complete the cycle, bringing the fingers back to the starting, point as illustrated. This path of movement gives an effective holding out action upon the edge of the sheet and the fingers are exposed to a minimum amount of heating action from the glass. They move inward over the sheet only a short distance before they are moved downwardly to the position illustrated and in such movement the base of the sheet is thinned and chilled when the fingers are brought to the position shown.- The substantially horizontal movement from this point on, while the fingers remain in the glass, tends to drag the edge out slightly. This result accomplished without undue disturbance or chilling of the glass and without picking it up upon the fingers, this being facilitated by the fact that the ends of the fingers remain out of the glass and only the convex surfaces are brought into contact with it. The slots 21 and 22 facilitate the adjustment of the fingers so that the cycle of movement may be moved in and out to compensate for changes in position of the edge of the sheet and to vary the distance which the fingers extend into the glass in their lowest extremes of movement. Due to the construction as illustrated, this may be accomplished without changing or adjusting the cycle of movement of the fingers. In operation, the device is partially shielded by the clay blocks 56 which are mounted for adjustment in and out over the side wall 57 of the tank. These blocks are designed to assist in regulating and maintaining the temperature of the glass bath therebeneath in the vicinity of the edges of the sheet, but they are also of advantage in protecting the edge device against overheating. Otheradvantages incident to the construction will be readily apparent to those skilled in the art.

What I claim is:

1. In combination with apparatus for drawing a glass sheet from a molten bath, means for preventing inward movement of the edge of the sheet comprising a pair of fingers spaced apart to straddle the edge of the sheet, and automatic means for moving the fingers at predetermined intervals downward over the edge of the sheet into the glass bath, then outward and up out of the glass.

2. In combination with apparatus for drawing a glass sheet from a molten bath, means for preventing inward movement of the edge of the sheet comprising a pair of fingers spaced apart to straddle the edge of the sheet, and automatic means for moving the fingers at predetermined intervals downward over the edge of the sheet into the glass bath, then outward and up out of the glass, the fingers being spaced apart a distance such that they engage and thin the tapering base or meniscus of the sheet.

3. In combination with apparatus for drawing a glass sheet from a molten bath means for preventing inward movement of the edge of the sheet comprising a pair of fingers spaced apart to straddle the edge of the sheet, and automatic means for moving the fingers at predetermined intervals downward over the edge of the sheet into the glass bath, then outward and up out of the glass with a pause between the movements with the fingers in a position remote from the molten bath.

4. In combination with apparatus for drawing a glass sheet from a molten bath, means for preventing inward movement of the edge of the sheet comprising a pair of fingers spaced apart to straddle the edge of the sheet, and automatic means for moving the fingers at predetermined intervals inward over the edge of the sheet, then down along such edge into the tapering base of the sheet, then, outward, and finally upward to starting position.

In combination with apparatus for drawing a glass sheet from a molten bath, means for preventing inward movement of the edge of the sheet comprising a pair of fingers spaced apart to straddle the edge of the sheet, and being curved so as topresent convex surfaces to the surface 01": the bath, and automatic means for moving the fingers at predetermined intervals, downward over the edge of the sheet into the glass bath, then outward and up out of the glass.

6. In combination with apparatus for drawing a glass sheet from a molten bath. means for preventing inward movement of the edge of the sheet comprising a pair of fingers spaced apart to straddle 'the edge of the sheet, automatic operating means for moving the fingers at predetermined intervals inward so as to straddle the edge of the sheet above the bath, then down into the glass at the base of the sheet and out ward away from the center line of the sheet, and a supporting framework for the fingers and their operating means mounted for adjustment with respect to the glass bath.

In testimony whereof, I have hereuntosubscribed my name this 29th day 01 Jany, 1923.

HARRY Gr. SLINGLUFF. 

